Method and apparatus for agglomerating materials



Aug l2 192% C. L. COLBERT METHOD AND APPARATUS FOR AGGLOMERATINGMATERIALS,

Filed May 19, 1922 3 Sheets-Sheet 1 O NH |||||.Hn Th INVENTOR B66ag/(M14 1a ATTORNEY:

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c. 1;. COLIBERT METHOD AND APBARATUS FOR AGGLOMERATING MATERIALS Aug"112 192% Filed May 19. 1922 3 Sheets-Shem. 2

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C. L. COLBERT METHOD AND APPARATUS FOR AGGLOMERATING MATERIALS Filed"may 19, 1922 :5 Sheets-Shwt 5 INVENTOR y cmwiw 004m [3 2 km @ATTORNEYJ'Patented Aug. l2, i924.

CLARENCE LEWIS COLBER-T, OF ELIZABETH, NEW JERSEY, ASSIG-NOR TO THEAMERI- CAN METAL COMPANY, LTD., 015 NEW YORK, N. Y., A CORPORATION OFNEW YORK.

METHOD AND APPARATUS FOR AGGLOMERATING MATERIALS.

Application filed. May 19, 1922.

To all whom it may concern.

Be it known that I, CLARENCE LEWIS CoLBEnT, a citizen of the UnitedStates, re: siding at Elizabeth, in the county of Union,

State of New Jersey, have invented certain new and useful Improvementsin Methods and Apparatus for Agglomerating Materials; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

This invention relates to the agglomeration of fine ores, concentrates,flue-dust and the like, and particularly to a method and apparatuswhereby material of the character described may be converted into a formmore readily adapted for handling and subsequent treatment for therecovery of the metallic values therein.

Numerous methods of agglomerating finely divided ore material have beensuggested heretofore. Some of them depend upon combustion of the sulphurcontent of the ore or of added combustible material. The sulphur contentof the material is frequently insuflicient and, moreover, it issometimes necessary to preserve the sulphur to ensure proper functioningof subsequent smelting operations. The addition of fuel is costlybecause coinbustion in sintering operations is inefiicient and wasteful.

To avoid the disadvantages mentioned, it has been proposed to mix anagglutinant such as tar, pitch or the like, or an agglomerating agentsuch as molten slag with the material. Both of these methods havedisadvantages, in addition to the expense involved, of providing lumpsor briquettes which crumble readily in the subsequent treatment or whichcontain a large amount of contaminating mineral impurities.

It has also been proposed to heat the finely divided material byshowering it through a flame and thereafter compacting it between rollsand to heat the material in a rotary kiln to a temperature which resultsin the formation of small lumps which are subsequently compacted intolarger lumps by passing through rolls. The former method isimpracticable because the time required for passage of the materialthrough the flame cannot be regulated according to the character of thematerial treated, and consequently the proper heating of the materialcannot be assured.

through the heating chamber.

Serial No. 562,063.

Furthermore, the furnace chamber will be quickly choked by accumulationof heated particles sticking to the walls thereof. The latter method hasbeen proven impracticable because any at tempt to heat the material to apoint which will cause formation of small lumps in the rotary furnaceresults in the formation of rings which adhere to the walls and preventfeeding of the material. These rings can only be removed by stopping andcooling the furnace so that workmen may enter to cut them away. Thecapacity of the apparatus is limited by the loss of time involved.

It is the object of the present invention to avoid all of thedifliculties mentioned and to provide a method of and apparatus foragglomerating which is efficient, economical and capable of applicationto a wide variety of finely divided materials.

My invention depends upon the regulation of the temperature and rate ofadvance of the material under treatment so that substantially nosintering or fritting of the material occurs during the heating thereof.The material is, however, brought to a plastic condition prior to itsdischarge from the heating chamber. In this plastic condition and whilestill in substantially its original divided form, the material issubjected to pressure preferably by passing between suitable rolls andis thus compacted into masses suitable for handling and subsequenttreatment in metallurgical furnaces and the like. Preferably the heatingis conducted in a rotary cylindrical furnace slightly inclined so thatthe material advances regularly The feeding of the material may bevaried by changing the rate of rotation to accommodate differences inthe sintering points of different materials. Heat is supplied bysuitable burner-s supplied with gaseous, liquid or pulverized solid fuelwhereby a flame or flames are projected into the lower end of thefurnace. Preferably pulverized coal is used. The products of combustionpass through. the heating chamber in the inverse direction to thedirection of travel of the material which is thus preheated andgradually brought to the desired temperature as it advances. To ensureproper heating of the material it has been found desirable to providethe kiln with a baflle at its lower end which directs the heatedcombustion products generated by the fuel burner, upon the material nearthe outlet from the kiln. This permits rapid heating of the material inthe last stage of its travel to a temperature which renders it plasticand avoids high ten'iperatures in the upper part of the kiln where suchtemperatures are undesirable. The material which is fed at a rate andsubjected only to a temperature which precludes sintering or frittingduring its passage through the heating chamber is quickly brought to aplastic condition and is discharged before it becomes agglomerated orhas an opportunity to adhere to the wall of the chamber and form ringstherein. The plastic material falls from the heating chamber into thecompact ing apparatus which preferably includes a pair of driven rollsbetween which the material passes, although other compacting means maybe employed. Y

In order'that the invention may be more readily understood I have shownby way of illustration a suitable apparatus for ,l'llGl practice of theinvention in the accompanying drawing, in which- Fig. 1is a plan view ofthe apparatus;

Fig. 2 is a side elevation partially in section thereof;

Fig. 3 is an end view of the apparatus;

Figs. 4 and 5 are detail views of one of the rolls; and

Figs. 6 and 7 are detail views of the other roll. V

Referring to the drawings, 1 indicates a rotary cylindrical kiln whichmay be supported and caused to rotate in any suitable manner; thestructure and mechanical arrangement of apparatus of this characterbeing well understood in the art. Material may be conveyed to the upperend of the kiln as required. At its lower end the/kiln is provided witha stationary combustion chamber 2 in which a burner 3 is mounted. Theburner maybe supplied with suitable fuel such as pulverized coal, andwith air or other combustion supporting agents. A baf fle 1 is providedin the combustion chamber to direct the products of combustiondownwardly toward the material as it approaches the outlet 5 throughwhichthe material; is

discharged. I

The rolls for applying pressure to the ln a terial are supported on aframe 6 and surrounded by a shell or casing 7 which serves to preventescape of the mate-rial except through a restricted outlet 9 at thebottom. thereof. A shaft 10 is supported in bearings 11 on'the frame andpasses'through the walls of the casing 8. A roll 12 is mounted on theshaft 10 within the casing. As shown in Figs. 6 and 7, this rollconsists of a hub 13, a web 14; and'rim "15, the rim being provided witha bearing surface 16 and with spaced projecting walls or peripheralflanges 17. The surface 16 is also provided with alternating projectionsand depressions 1S and 19 to prevent slippage of the roll on thematerial as it passes thereover.

A. complementary roll 20 is supported on a shaft 21 mounted in bearings22 at the ends of arms 23 projecting from and secured to a rock shaft 24which is mounted in bearings 25 on the frame. An arm 26 is secured tothe shaft 2% and supports a weight 27 provided with a set screw 28whereby the weight may be secured in any adjusted position along thelength of the arm. This weight forms a counterbalance for the roll 20and by moving it to one or another position the pressure of the roll 20downward upon the material passing over the roll 12 may be regulated asdesired. As shown in Figs. L and 5, the roll 20 comprises a hub 29, web30 and rim 31, the latter being provided with alternating projectionsand dopressions 32 and adapted to cooperate with the projections anddepressions on the roll 12 to insure rotation of the roll 20 and toprevent slippage of the roll upon the material to be compressed.

The shaft 10 carries at its end a gear 3 1: meshing with a pinion which.is loosely mounted on a. shaft 36 rotating in bearings 37 on the frame6. A clutch member is splined on the shaft 36 and may be movedlengthwise of the shaft by a shifter arm 38 to cause the clutch member35 to engage or disengage clutch jaws formed on the pinion 35 andthereby connect or disconnect the pinion to or from the shaft 36. Theshaft 36 also carries a sprocket wheel 39 driven by a chain 40 from. asprocket wheel 41 on a power shaft 42 which. is mounted in bcarin gs andprovided with apullcy or othermeans for driving it.

The material which is heated in the kiln to bring it to a plasticcondition is discharged in that condition but still in its divided forminto the space between the rolls 12 and 20 and between the flanges 17 ofthe roll 12. The roll 12 is rotated through the gearing above describedincluding the pinion and gear 34: so that the material delivered betweenthe rolls is subjected to pressure. Downward pressure of the roll 20upon the material is regulated by the counter-weight 27 and issufiiciont to compact the material as it passes between the rolls. Thecooperating projections on the. rolls prevent slippage thereofrelatively to the material. lVhenever it may be necessary by reason ofchanges in the rate of discharge of the material from the kiln, the roll20 may move toward or away from the roll 12 to adjust itself to thevolume of material delivered. The con'lpactcd material is ,deliveredthrough the outlet 9 from the (us ing 8.

()bviously the temperatures and the rate at which the material is fedthrough the apparatus will vary with the characteristics of thatmaterial, particularly the temperature at which it becomes plastic andtends to ag glomerate by the sticking together of the particles. Thenecessary regulation to en sure treatment of any given material can ofnecessity be determined only by trial. IV hen the factors areascertained, however, materials of the same character can there after betreated successfully without dil'liculty or more careful observationthan is usually employed in the operation of similar methods.

My method is characterized and distinguished from all other methods ofagglomerating materials by the fact that it is possible thereby toensure proper regulation and to prevent premature agglomeration and theformation of rings in the heating chamber. The method may, therefore, beoperated continuously and without loss of time incident to the removalof such rings. Economical treatment of the material is assured becausethe heat is applied at its most effective point and, moreover, the Wasteresulting from radiation in attempting to maintain a considerable zoneof the heating chamber at a temperature suitable for agglomeration isgreatly reduced. These and other advantages of the method make it highlysatisfactory in its practical application to the treatment of finelydivided materials.

While the method may be practiced with apparatus other than thatillustrated, the apparatus described is well adapted to theaccomplishment of the objects noted and is preferred as the best meansof commercially utilizing the invention.

Various changes may be made in the details of operation and in theapparatus used within the scope of the accompanying claims withoutdeparting from the invention or sacrificing any of the advantagesthereof.

I claim:

1. A method of agglomerating ores, concentrates, flue-dust and likedivided material, which comprises causingthe material to advance througha heating chamber, subjecting it to gradual heating therein, regulatingthe rate of travel and the temperature of the material in accordancewith its physical characteristics to avoid fusion but so as to dischargeit from the chamber in a plastic condition and in substantially itsoriginal divided form, and subjecting the divided material to pressurewhile in the plastic condition.

2. A method of agglomerating ores, concentrates, flue-dust and likedivided ma terial, which comprises causing the material to advancethrough a heating chamber, subjecting it to gradual heating therein to atemperature lower than that at which the material sinters or frits,rapidly increasing the temperature of the material to bring it to aplastic condition without fusion and While retaining substantially itsoriginal divided form prior to discharge of the material from thechamber, and subjecting the divided material to pressure while in theplastic condition.

3. A method of agglomerating ores, concentrates, flue-dust and likedivided material, which comprises heating the material in an inclinedrotary cylindrical heating chamber, regulating the rate of travel of thematerial so that it is discharged in a'plastic condition and in itsoriginal divided form with substantially no agglomeration, andsubjecting the divided material to pressure while in a plasticcondition.

l. In an apparatus for agglomerating ores, concentrates, flue-dust andlike material, the combination of a kiln having a discharge outlet,means for supplying combusti'on products to the kiln at the outletthereof, and a baflle arranged adjacent the discharge outlet to directthe combustion products upon the material prior to discharge thereof,and means for applying pressure to the material as it is discharged.

5. In an apparatus for agglomerating ores, concentrates, flue-dust andlike ma terial, the combination of a rotary cylindricalkiln, astationary combustion chamher having a discharge outlet at the dischargeend of the kiln, means for supplying combustion products to thecombustion chamber, a battle in the combustion chamber adjacent thedischarge outlet to direct the combustion products upon the materialprior to discharge thereof, and means for applying pressure to thematerial as it is discharged.

In testimony whereof I atfix my signature.

CLARENCE LEWIS COLBERT.

